userns: Convert ext3 to use kuid/kgid where appropriate

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

4 files changed, 52 insertions, 28 deletions

diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c
index baac1b129fba..25cd60892116 100644
--- a/fs/ext3/balloc.c
+++ b/fs/ext3/balloc.c
@@ -1439,8 +1439,9 @@ static int ext3_has_free_blocks(struct ext3_sb_info *sbi, int use_reservation)
         free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
         root_blocks = le32_to_cpu(sbi->s_es->s_r_blocks_count);
         if (free_blocks < root_blocks + 1 && !capable(CAP_SYS_RESOURCE) &&
-                !use_reservation && sbi->s_resuid != current_fsuid() &&
-                (sbi->s_resgid == 0 || !in_group_p (sbi->s_resgid))) {
+                !use_reservation && !uid_eq(sbi->s_resuid, current_fsuid()) &&
+                (gid_eq(sbi->s_resgid, GLOBAL_ROOT_GID) ||
+                 !in_group_p (sbi->s_resgid))) {
                 return 0;
         }
         return 1;
diff --git a/fs/ext3/ext3.h b/fs/ext3/ext3.h
index b6515fd7e56c..7977973a24f0 100644
--- a/fs/ext3/ext3.h
+++ b/fs/ext3/ext3.h
@@ -243,8 +243,8 @@ struct ext3_new_group_data {
  */
 struct ext3_mount_options {
         unsigned long s_mount_opt;
-        uid_t s_resuid;
-        gid_t s_resgid;
+        kuid_t s_resuid;
+        kgid_t s_resgid;
         unsigned long s_commit_interval;
 #ifdef CONFIG_QUOTA
         int s_jquota_fmt;
@@ -637,8 +637,8 @@ struct ext3_sb_info {
         struct buffer_head ** s_group_desc;
         unsigned long  s_mount_opt;
         ext3_fsblk_t s_sb_block;
-        uid_t s_resuid;
-        gid_t s_resgid;
+        kuid_t s_resuid;
+        kgid_t s_resgid;
         unsigned short s_mount_state;
         unsigned short s_pad;
         int s_addr_per_block_bits;
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 10d7812f6021..a09790a412b1 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -2891,6 +2891,8 @@ struct inode *ext3_iget(struct super_block *sb, unsigned long ino)
         transaction_t *transaction;
         long ret;
         int block;
+        uid_t i_uid;
+        gid_t i_gid;
 
         inode = iget_locked(sb, ino);
         if (!inode)
@@ -2907,12 +2909,14 @@ struct inode *ext3_iget(struct super_block *sb, unsigned long ino)
         bh = iloc.bh;
         raw_inode = ext3_raw_inode(&iloc);
         inode->i_mode = le16_to_cpu(raw_inode->i_mode);
-        inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
-        inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
+        i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
+        i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
         if(!(test_opt (inode->i_sb, NO_UID32))) {
-                inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
-                inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
+                i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
+                i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
         }
+        i_uid_write(inode, i_uid);
+        i_gid_write(inode, i_gid);
         set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
         inode->i_size = le32_to_cpu(raw_inode->i_size);
         inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime);
@@ -3068,6 +3072,8 @@ static int ext3_do_update_inode(handle_t *handle,
         struct ext3_inode_info *ei = EXT3_I(inode);
         struct buffer_head *bh = iloc->bh;
         int err = 0, rc, block;
+        uid_t i_uid;
+        gid_t i_gid;
 
 again:
         /* we can't allow multiple procs in here at once, its a bit racey */
@@ -3080,27 +3086,29 @@ again:
 
         ext3_get_inode_flags(ei);
         raw_inode->i_mode = cpu_to_le16(inode->i_mode);
+        i_uid = i_uid_read(inode);
+        i_gid = i_gid_read(inode);
         if(!(test_opt(inode->i_sb, NO_UID32))) {
-                raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));
-                raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid));
+                raw_inode->i_uid_low = cpu_to_le16(low_16_bits(i_uid));
+                raw_inode->i_gid_low = cpu_to_le16(low_16_bits(i_gid));
 /*
  * Fix up interoperability with old kernels. Otherwise, old inodes get
  * re-used with the upper 16 bits of the uid/gid intact
  */
                 if(!ei->i_dtime) {
                         raw_inode->i_uid_high =
-                                cpu_to_le16(high_16_bits(inode->i_uid));
+                                cpu_to_le16(high_16_bits(i_uid));
                         raw_inode->i_gid_high =
-                                cpu_to_le16(high_16_bits(inode->i_gid));
+                                cpu_to_le16(high_16_bits(i_gid));
                 } else {
                         raw_inode->i_uid_high = 0;
                         raw_inode->i_gid_high = 0;
                 }
         } else {
                 raw_inode->i_uid_low =
-                        cpu_to_le16(fs_high2lowuid(inode->i_uid));
+                        cpu_to_le16(fs_high2lowuid(i_uid));
                 raw_inode->i_gid_low =
-                        cpu_to_le16(fs_high2lowgid(inode->i_gid));
+                        cpu_to_le16(fs_high2lowgid(i_gid));
                 raw_inode->i_uid_high = 0;
                 raw_inode->i_gid_high = 0;
         }
@@ -3262,8 +3270,8 @@ int ext3_setattr(struct dentry *dentry, struct iattr *attr)
 
         if (is_quota_modification(inode, attr))
                 dquot_initialize(inode);
-        if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
-                (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
+        if ((ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, inode->i_uid)) ||
+            (ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, inode->i_gid))) {
                 handle_t *handle;
 
                 /* (user+group)*(old+new) structure, inode write (sb,
diff --git a/fs/ext3/super.c b/fs/ext3/super.c
index cf0b5921cf0f..94ef7e616129 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -617,13 +617,15 @@ static int ext3_show_options(struct seq_file *seq, struct dentry *root)
                 seq_puts(seq, ",grpid");
         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT3_DEFM_BSDGROUPS))
                 seq_puts(seq, ",nogrpid");
-        if (sbi->s_resuid != EXT3_DEF_RESUID ||
+        if (!uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT3_DEF_RESUID)) ||
             le16_to_cpu(es->s_def_resuid) != EXT3_DEF_RESUID) {
-                seq_printf(seq, ",resuid=%u", sbi->s_resuid);
+                seq_printf(seq, ",resuid=%u",
+                                from_kuid_munged(&init_user_ns, sbi->s_resuid));
         }
-        if (sbi->s_resgid != EXT3_DEF_RESGID ||
+        if (!gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT3_DEF_RESGID)) ||
             le16_to_cpu(es->s_def_resgid) != EXT3_DEF_RESGID) {
-                seq_printf(seq, ",resgid=%u", sbi->s_resgid);
+                seq_printf(seq, ",resgid=%u",
+                                from_kgid_munged(&init_user_ns, sbi->s_resgid));
         }
         if (test_opt(sb, ERRORS_RO)) {
                 int def_errors = le16_to_cpu(es->s_errors);
@@ -967,6 +969,8 @@ static int parse_options (char *options, struct super_block *sb,
         substring_t args[MAX_OPT_ARGS];
         int data_opt = 0;
         int option;
+        kuid_t uid;
+        kgid_t gid;
 #ifdef CONFIG_QUOTA
         int qfmt;
 #endif
@@ -1000,12 +1004,23 @@ static int parse_options (char *options, struct super_block *sb,
                 case Opt_resuid:
                         if (match_int(&args[0], &option))
                                 return 0;
-                        sbi->s_resuid = option;
+                        uid = make_kuid(current_user_ns(), option);
+                        if (!uid_valid(uid)) {
+                                ext3_msg(sb, KERN_ERR, "Invalid uid value %d", option);
+                                return -1;
+
+                        }
+                        sbi->s_resuid = uid;
                         break;
                 case Opt_resgid:
                         if (match_int(&args[0], &option))
                                 return 0;
-                        sbi->s_resgid = option;
+                        gid = make_kgid(current_user_ns(), option);
+                        if (!gid_valid(gid)) {
+                                ext3_msg(sb, KERN_ERR, "Invalid gid value %d", option);
+                                return -1;
+                        }
+                        sbi->s_resgid = gid;
                         break;
                 case Opt_sb:
                         /* handled by get_sb_block() instead of here */
@@ -1651,8 +1666,8 @@ static int ext3_fill_super (struct super_block *sb, void *data, int silent)
         }
         sb->s_fs_info = sbi;
         sbi->s_mount_opt = 0;
-        sbi->s_resuid = EXT3_DEF_RESUID;
-        sbi->s_resgid = EXT3_DEF_RESGID;
+        sbi->s_resuid = make_kuid(&init_user_ns, EXT3_DEF_RESUID);
+        sbi->s_resgid = make_kgid(&init_user_ns, EXT3_DEF_RESGID);
         sbi->s_sb_block = sb_block;
 
         blocksize = sb_min_blocksize(sb, EXT3_MIN_BLOCK_SIZE);
@@ -1716,8 +1731,8 @@ static int ext3_fill_super (struct super_block *sb, void *data, int silent)
         else
                 set_opt(sbi->s_mount_opt, ERRORS_RO);
 
-        sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
-        sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
+        sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
+        sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
 
         /* enable barriers by default */
         set_opt(sbi->s_mount_opt, BARRIER);